Inhaler devices for dispensing therapeutic substances via the respiratory tract, in particular, for pulmonary delivery in treating local or systemic diseases are commercially available. For example, nebulizers, devices containing propellants, and dry powder inhalers have been used for the treatment of diseases, such as asthma, respiratory tract infections and systemic disease such as diabetes.
The efficiency of delivering a required dosage of a therapeutic substance to a patient in treating a disease depends on the efficiency of the device, and overall delivery can be enhanced by providing proper feedback mechanisms to a patient during use of the device to teach, for example, proper inhalation techniques to a patient. Improper use of the devices and poor inhalation techniques can lead to lack of efficacy in treating a disease, for example, by administering lower dosages of a therapeutic substance than intended or higher dosages of a therapeutic substance which can be harmful to a patient. To effectively deliver therapeutic substances to the respiratory tract, a patient or user can be trained or coached to use the device in an appropriate manner.
Dry powder inhalers used to deliver medicaments to the lungs contain a dosing system for a powder formulation usually either in bulk supply or quantified into individual doses stored in unit dose compartments, like hard gelatin capsules, cartridges, or blister packs. Dosing reproducibility requires that the drug formulation is uniform and that the dose can be delivered to the patient with consistent and reproducible results. Therefore, dosing can be improved by optimizing discharge of a formulation, which is effectuated, for example, by having patients perform proper inhalation maneuvers.
Devices for training patients to properly deliver therapeutic substances by the pulmonary tract are described, for example, in U.S. Pat. No. 5,333,106, which discloses an apparatus for interactive training of a patient in use of an aerosol inhaler, including a feedback display based upon air flow versus volume data using a proper sequence of inhalation steps. Further, U.S. patent application Ser. No. 10/759,859 (Publication No. US 2004/0187869) discloses a training device for medicament inhalers, for example, dry powder inhalers, which is based on measuring pressure differential and displaying a single value corresponding to both inhalation rapidity and inhalation flow rate peak, and includes a dry powder inhaler simulator.
Dry powder inhaler and cartridge systems such as those describe in U.S. Pat. Nos. 7,305,986 and 7,464,706, the disclosures of which are incorporated herein by reference in their entirety for all they teach regarding dry powder inhalers, can generate primary drug particles or suitable inhalation plumes during an inspiratory maneuver by deagglomerating a powder formulation within the inhaler and capsule or cartridge. The benefits of delivering drugs via pulmonary circulation are numerous including rapid entry into arterial circulation, avoidance of first pass drug degradation by liver metabolism, and ease of use, for example, lack of discomfort compared to other routes of administration such as by injection. These devices have been in use in clinical settings and patients have been properly trained on the use of such inhalers.
There is a need in the art for improvements in design and manufacture of a device for training subjects in proper use of an inhalation system; monitoring patients during use of an inhalation system, monitoring the performance of an inhalation system, such as presence of leakage or defects, and capable of being coupled to a system for reproducing a patient's inhalation profile. The present disclosure presents apparatus and methods to achieve these goals.